The need for improving brush making equipment can best be described by comparing and describing conventional staple-set machinery and fusing machinery with the new and improved machinery of this invention.
Conventional staple-set brush picking machinery (forming filament tufts) employs a picker means which removes only a single filament tuft at a time from a stock box or feed mechanism by first entering the stock box approximately at its mid-section (lateral to the parallel filament) and assembling or picking a given amount of filament at the filaments mid-section. Such filament stock boxes are disclosed in brush machinery patents, for example, U.S. Pat. Nos. 2,433,191 (Baumgartner) and 3,059,972 (Schmidt).
The picker then proceeds to transport the predetermined volume of the parallel filament to a suitable means for doubling the filament at its mid-section, just prior to stapling, thus resulting in a tuft having a U-shaped configuration, wherein both ends of an individual filament are located at the working end of the resultant. A staple or anchor is then inserted through the U-shaped loop and the tuft is forced into a pre-drilled or molded hole in a brush block.
The conventional fusing brush machinery (forming all the filament tufts in a given brush simultaneously) employs a picking device made up of one or more picking elements which move in one direction into a mass of pre-cut synthetic filament parallel to the filaments' length and removes all the necessary tufts required for a given brush Such picking devices and machinery are disclosed in brush patents, for example, U.S. Pat. Nos. 3,471,202 (Lewis), Re. 27,455 (Lewis), 4,255,224 (Lorenz) and 4,693,519 (Lewis). Also, there have been various improvements in picking devices, stock boxes, but the one major problem which this instant invention overcomes is the ability to insert a picking device containing at least one picking element into a filament stock box to select the proper predetermined amount of cut-to-length filament at its end. Filling the picking element in one instant of time without causing stray individual filament strands, which first come into contact with the front-end of the picking element, to become pushed through the mass of parallel filament by the picker element as it works its way into the mass of said filament towards the back of the stock box is a major problem. This causes the stray filaments to bend over and/or (1) fall out of the rear of said stock box; (2) move out of parallel attitude causing the mass of parallel filaments to mix in all directions; and (3) bend so that when the picking device is retracted from the stock box the filaments contained within the picking element or elements are held by the stray bent individual filament, thus causing the filaments within the picking element to remain in the stock box.
Individual filaments that become bent, misaligned or disoriented within the said stock box cause voids and pockets of unaligned filament. This then causes picking misses or unfilled picker elements In order to keep the unpicked filament parallel and flowing through the stock box, it becomes necessary to constantly clean the bent and disoriented filament from the mass by pulling out the bent pieces, and aligning the parallel relationship of the remaining mass without disrupting the density of the unpicked filament during each subsequent picking cycle.
Improvements in filament flow through stock boxes have been disclosed in U.S. Pat. Nos. 4,693,519 (Lewis) and 4,696,519 (Lewis) and are hereby incorporated by reference.
To date, all longitudinal picking of cut-to-length brush filament has been a single, one-motion index of a picking element into and through the filament stock box while simultaneously causing the filament, within the said box, to oscillate back and forth from front to back of the box.